Need help in developing Asus Xonar Essence ST driver

[SchwarzerVossatka]

Hello. I've recently found this (https://github.com/polachok/xonar-freebsd/) driver for a family of "Asus Xonar" sound cards. Currently only Asus Xonar Essence STX is supported, but I want ST, so I made this patch: http://pastebin.com/Qb8BWPEN , according to an OSS driver (http://sourceforge.net/p/opensound/merc ... _cmi878x.c). The system detects the card and can direct sound output both to line out and headphones (the card produces a mechanical "click" sound in process), but there is no playback.

If I remove (#if 0/#endif) here

+#if 0
+               pcm1796_write(sc, XONAR_ST_CLOCK, 0x5, 0x8);
+               pcm1796_write(sc, XONAR_ST_CLOCK, 0x2, 0x0);
+               pcm1796_write(sc, XONAR_ST_CLOCK, 0x5, 0x1);
+#endif

the system will panic. These lines of code correspond to cs2000_init () function from OSS driver. Crash dump looks like:

> kgdb kernel vmcore.3 
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This GDB was configured as "amd64-marcel-freebsd"...

Unread portion of the kernel message buffer:
pcm0: <Asus Xonar Essence ST (AV100)> port 0xe800-0xe8ff irq 21 at device 6.0 on pci6
pcm0: AC97 codec0 found
pcm0: MPU401 found
can't re-use a leaf (buffersize)!
pcm0: channel0 (Multichannel)


Fatal trap 9: general protection fault while in kernel mode
cpuid = 1; apic id = 11
instruction pointer     = 0x20:0xffffffff80d30552
stack pointer           = 0x28:0xfffffe023a736160
frame pointer           = 0x28:0xfffffe023a7361b0
code segment            = base 0x0, limit 0xfffff, type 0x1b
                        = DPL 0, pres 1, long 1, def32 0, gran 1
processor eflags        = interrupt enabled, resume, IOPL = 0
current process         = 1536 (kldload)
trap number             = 9
panic: general protection fault
cpuid = 1
KDB: stack backtrace:
#0 0xffffffff808826b0 at kdb_backtrace+0x60
#1 0xffffffff8084a145 at panic+0x155
#2 0xffffffff80c345e2 at trap_fatal+0x3a2
#3 0xffffffff80c3421f at trap+0x7bf
#4 0xffffffff80c1b2e2 at calltrap+0x8
#5 0xffffffff82978066 at sndbuf_alloc+0x46
#6 0xffffffff8296c677 at xonar_chan_init+0x157
#7 0xffffffff8297b10b at chn_init+0x3ab
#8 0xffffffff8298954f at pcm_chn_create+0x27f
#9 0xffffffff82989859 at pcm_addchan+0x59
#10 0xffffffff8296bc84 at xonar_attach+0xab4
#11 0xffffffff80879b22 at device_attach+0x3a2
#12 0xffffffff8062330a at pci_driver_added+0xfa
#13 0xffffffff80877d0d at devclass_driver_added+0x7d
#14 0xffffffff80877c6c at devclass_add_driver+0x11c
#15 0xffffffff80835aab at module_register_init+0xfb
#16 0xffffffff8082b36e at linker_load_module+0xb6e
#17 0xffffffff8082c577 at kern_kldload+0xc7
Uptime: 1h29m45s
Dumping 705 out of 8139 MB:..3%..12%..21%..32%..41%..53%..62%..71%..82%..91%

Reading symbols from /boot/kernel/sem.ko.symbols...done.
Loaded symbols for /boot/kernel/sem.ko.symbols
Reading symbols from /boot/modules/nvidia.ko...done.
Loaded symbols for /boot/modules/nvidia.ko
Reading symbols from /boot/modules/vboxdrv.ko...done.
Loaded symbols for /boot/modules/vboxdrv.ko
Reading symbols from /boot/kernel/zfs.ko.symbols...done.
Loaded symbols for /boot/kernel/zfs.ko.symbols
Reading symbols from /boot/kernel/opensolaris.ko.symbols...done.
Loaded symbols for /boot/kernel/opensolaris.ko.symbols
Reading symbols from /home/vasily/xonar-freebsd/xonar-dump/snd_xonar.ko...done.
Loaded symbols for /home/vasily/xonar-freebsd/xonar-dump/snd_xonar.ko
Reading symbols from /boot/kernel/sound.ko.symbols...done.
Loaded symbols for /boot/kernel/sound.ko.symbols
#0  doadump (textdump=<value optimized out>) at pcpu.h:219
219     pcpu.h: No such file or directory.
        in pcpu.h
(kgdb) bt
#0  doadump (textdump=<value optimized out>) at pcpu.h:219
#1  0xffffffff80849dc0 in kern_reboot (howto=260) at /usr/src/sys/kern/kern_shutdown.c:447
#2  0xffffffff8084a184 in panic (fmt=<value optimized out>) at /usr/src/sys/kern/kern_shutdown.c:754
#3  0xffffffff80c345e2 in trap_fatal (frame=<value optimized out>, eva=<value optimized out>) at /usr/src/sys/amd64/amd64/trap.c:882
#4  0xffffffff80c3421f in trap (frame=<value optimized out>) at /usr/src/sys/amd64/amd64/trap.c:224
#5  0xffffffff80c1b2e2 in calltrap () at /usr/src/sys/amd64/amd64/exception.S:232
#6  0xffffffff80d30552 in bus_dmamem_alloc (dmat=0xffff00003df63500, vaddr=0xfffff8017fa5d408, flags=5, mapp=0xfffff8017fa5d478) at /usr/src/sys/x86/x86/busdma_machdep.c:505
#7  0xffffffff82978066 in sndbuf_alloc (b=0xfffff8017fa5d400, dmatag=<value optimized out>, dmaflags=<value optimized out>, size=<value optimized out>) at /usr/src/sys/modules/sound/sound/../../../dev/sound/pcm/buffer.c:101
#8  0xffffffff8296c677 in xonar_chan_setformat () from /home/vasily/xonar-freebsd/xonar-dump/snd_xonar.ko
#9  0x000000013a736230 in ?? ()
#10 0xfffff8017f75ea90 in ?? ()
#11 0xfffff8017f75ea90 in ?? ()
#12 0xfffff80008fc2c00 in ?? ()
#13 0xfffff8017fa5d400 in ?? ()
#14 0xfffff8017fa5d400 in ?? ()
#15 0x0000000000000001 in ?? ()
#16 0xfffff8017fa5d000 in ?? ()
#17 0xfffffe023a736270 in ?? ()
#18 0xffffffff8297b10b in chn_init (c=0xfffff8017f75ea00, devinfo=0xfffff8017f75ea90, dir=<value optimized out>, direction=0) at channel_if.h:29
Previous frame identical to this frame (corrupt stack?)
Current language:  auto; currently minimal
(kgdb) frame 6
#6  0xffffffff80d30552 in bus_dmamem_alloc (dmat=0xffff00003df63500, vaddr=0xfffff8017fa5d408, flags=5, mapp=0xfffff8017fa5d478) at /usr/src/sys/x86/x86/busdma_machdep.c:505
505             if (flags & BUS_DMA_NOWAIT)
(kgdb) q

It turns out that panic is caused by this line:

                pcm1796_write(sc, XONAR_ST_CLOCK, 0x2, 0x0);

I can't understand what is going on here. Here you can download my kernel/crash dump/module: https://drive.google.com/file/d/0B1NArWn4pLpxcDlVSDBpZEE3YkU/edit?usp=sharing

Can anyone make a suggestion what I am doing wrong?